Communication means safer traffic

Today’s vehicles can be equipped with various passive and active safety systems like ABS brakes and collision alarms. But they can only react to dangers they themselves ‘sense’ or ‘see’ via the vehicle’s own sensors, radar, or camera.

A system for communication between cars is more proactive, offering an entirely different degree of advance planning and enhancing the chances of avoiding accidents, especially at intersections and on ramps. But there are many technical problems that need to be solved before this can be come a reality.

Ioan Chisalita at the Department of Computer and Information Science has created a system based on a distributed communication protocol that enables vehicles to create virtual clusters depending on the current traffic situation. He is presenting his solution in a doctoral dissertation titled Communication and Networking Techniques for Traffic Safety Systems.

Cars that all are equipped with a camera, GPS, and various sensors transmit signals up to ten times per second. Data on position, speed, road surface, braking, turn-indicator position, etc. are exchanged among the vehicles within a 300-meter radius. A computer in the car processes the information and warns the driver. It is also possible to create a system that takes control of the car as a last resort.

For this to function, a uniform standard is needed for wireless communication, like WLAN. The system can also include servers along the sides of the road to provide information about the traffic status. In Japan a system like this is already in place along expressways to receive and transmit information via radio and infra-red light.

The communication system has been tested in a traffic simulator with a number of different scenarios, based on authentic accidents from an American database.

The dissertation will be publicly defended on Friday, June 2, 2006 at 10:15 a.m. in The Vision Hall, Building B, Linköping University, Campus Valla.